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A026045 a(n) = (d(n)-r(n))/5, where d = A026043 and r is the periodic sequence with fundamental period (0,2,3,0,0).

%I A026045 #8 Jun 13 2015 00:49:05
%S A026045 9,13,19,28,39,53,70,91,117,147,182,222,268,321,380,446,519,600,690,
%T A026045 788,895,1011,1137,1274,1421,1579,1748,1929,2123,2329,2548,2780,3026,
%U A026045 3287,3562,3852,4157,4478,4816,5170,5541,5929,6335,6760,7203,7665,8146,8647,9169,9711,10274,10858,11464
%N A026045 a(n) = (d(n)-r(n))/5, where d = A026043 and r is the periodic sequence with fundamental period (0,2,3,0,0).
%H A026045 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1,0,1,-3,3,-1).
%F A026045 a(n)=(n + 5)*(2*n^2 + 11*n + 54)/30 - (1 + ( - 1/2 - 1/10*5^(1/2))*cos(2*n*Pi/5) + (1/10*(3*(5 - 5^(1/2))^(1/2) + 2*(5 + 5^(1/2))^(1/2))*2^(1/2))*sin(2*n*Pi/5) + (1/10*5^(1/2) - 1/2)*cos(4*n*Pi/5) + (1/10*(2*(5 - 5^(1/2))^(1/2) - 3*(5 + 5^(1/2))^(1/2))*2^(1/2))*sin(4*n*Pi/5))/5 [From _Richard Choulet_, Dec 14 2008]
%F A026045 G.f. x*( 9-14*x+7*x^2+x^3-x^4-8*x^5-6*x^7+14*x^6 ) / ( (x^4+x^3+x^2+x+1)*(x-1)^4 ). - _R. J. Mathar_, Jun 22 2013
%Y A026045 A152857 [From _Richard Choulet_, Dec 14 2008]
%K A026045 nonn
%O A026045 1,1
%A A026045 _Clark Kimberling_